Jack



C.H. HOWLAND-SHEAR MAN.

' JACK. APPLICATION FILED OCT. 21. 1920.

1,400,605, Patented Dec. 20, 1921.

2 SHEET$-SHEET I. 6/ F 49 FIG. 1.

wmvzss- INVENTOR.

UNETED STATS CHARLES H. ROWLAND-SHEARMAN, 01E INDIANAPOLIS, INDIANA.

JACK.

Specification of Letters Patent.

Patented Dec. 20, 1921.

Application filed October 21, 1920. Serial No. 418,454.

To all wizom it may concern:

Be 1t known that 1, CHARLES H. HOWLAND- SHEARMAN, a citlzen of the Unlted States, re-

siding at Indianapolis, in the county of Marion and State of Indiana, have invented certain new and useful Improvements in Jacks, of which the following is a specification.

The objects of my invention are as follows: first, to provide a mechanism for jacks which shall be capable of exerting a power equal to that of the most powerful previous jacks of different construction, but of operating at much greater speed; second, to furnish a jack of sufficient compactness and of adequate power for the heaviest classes of service, so as to adapt it to be carried as a part of the regular equipment of motortrucks, cabooses, wrecking-cars etc.; and third, to supply a form of ack adaptable to use in handling the parts of heavy machinery, in assembling-shops for emergency work in connection with cranes, and for similar requirements.

I accomplish the objects referred to by means of the mechanism illustrated in the accompanying drawings, in which Figure 1, is a side elevation of one of my jacks of the ten-ton capacity; Fig. 2 is a longitudinal section of the same jack s own in Fig. 1, taken on the line 2-2 Fig. 3 looking in the direction of the arrows, showing the general arrangement of the complete mechanism; Fig. 3 is a transverse sectional view, taken of the line 3-3 Fig. 2 looking in the direction of the arrows, showing in defail, the dash-pot mechanism and ram with the guides therefor and portions of the pawlyoke. lifting-beam and walking-link constructions; Fig. 4 is a transverse sectional view of the same jack, taken on the line 4-.4l- Fig. 2 looking in the direction of the arrows, showing details of the primary tractor-levers, secondary tractor-levers, and lifting-beam, and illustrating the method of assembling the bifurcated frame, in which I prefer to house the mechanism of my invention for its protection against dirt and moisture; and Fig. 5 is a transverse sectional view, taken on the line 5-5 Fig. 2 looking in the direction of the arrows, showing details of the power-crank, connecting-link, primary tractor-levers, and lifting beam.

Similar numerals refer to similar parts throughout the several views.

Referring to Figs. 1, 2, and 5, 1 is the bifurcated frame of my jack, consisting of the two halves 2 and 3, each preferably machined and fitted tightly together with a cement in the joints for exclusion of injurious substances. A demountable handle as 4, is inserted in the socket 5 of the power-crank 6, pivoted on the fulcrum-pin 7, the threaded reductions on the ends of which are piercingly secured through the respective halves 2 and 3 of the frame 1 by nuts as 8 and 9, causing said fulcrum-pin to also function as a member for assembling said frame.

Referring to Figs. 2, 4 and 5, said powercrank 6 bears a slot 10,, within which is articulated by the connecting-pin 11 the connecting-link 12, the opposite end of which link is commonly jointed by means of the knuckle-pin 13, between the lower end of the slotted suspension-arm 14c, and the upper end of the duplex delivery-arm l5 of the primary tractor levers l6, suspended upon the primary suspension-pin 17, and the reduced threaded ends of the latter pin are piercingly secured through the halves 2 and 3 of the frame 1 by the respective nuts 18, 19, so as to also function aS an assembling member for said frame. The lower end of said duplex delivery-arm 15 is commonly articulated by means of the secondary knucklepin 20 intermediately between the inner ends of the suspension-arm 21 and delivery-arm 22 of the secondary tractor-levers 23 journaled on the secondary fulcrum-pin 24; the two halves of the lower end of said duplex delivery-arm' 15 of said primary tractorlevers 16 being spaced by the collar 25, for correct parallelism with said primary sus pension arm 14:, as especially shown in Fig. l. The said secondary suspe11sion-pin2t likewise bears threaded reductions at its ends piercingly secured by nuts as 26, exterior to either half of the bifurcated frame, as indicated by Fig. 1.

By comparison of Figs. 2, 41', and 5 it will be seen that while the halves of the duplex secondary suspension-arm 21 are checked closely contiguous to the inside face of the frame 1, inclosing between them the halves of the duplex secondary delivery arm 22, the latter are in turn inclosed between the lower ends of the two halves of the duplex liftingbeam 27 between which they are spaced by the internal spacer 28 and to which they are articulated by the secondary delivery-pin 29. This arrangement enables the halves of said duplex lifting-beam 27 to in turn be member to said frame. Clearanceopenings closely checked up against thin washers as 30 close to the inner faces of the respective halves 2 and 3 of the bifurcated frame, through which the beam fulcrum-pin 31 is piercingly secured by nuts 32, 33, so as to cause it to also function as an assembling end of the lifting-beam 2T'is articulated'by the yoke-pin 35 to the duplex pawl-yoke 36 having secured therein the inner pawl-pin 37 on which is mounted the inner liftingpawl 38V and the outer pawl-pin 39 on which is pivoted the outer lifting-pawl d0, respectively adapted to engage with the inner ratchet teeth l1, and outer ratchet teeth t2 on the ram 13, as especially indicated in Fig. 2. The inner spring-lug 44, contains the inner compression spring {t5 which keeps the inner lifting-pawl 38 normallyin' contact with said inner ratchet teeth tl, and the outer spring-lug 4:6 contains the outer com pression spring 47 which keeps the outer lifting-pawl 4E0 "normally in engagement with the outer ratchet teeth 42. Both of said lugs are secured to the halves of theiduplex lifting-beam 27 by cap screws as ets'inFig. 3.

Referring to Figs. 1, 2, and3, the inner sustaining pawl fulcrum-pin 49 having mounted thereon the inner sustaining pawl 50 and the outer sustaining-pawl fulcrumpin 51 having mounted thereon the outer sustaining-pawl 52 are piercingly secin'ed through the respective halves 2 and 3 of the frame by threaded reductions furnished with nuts as 53 Fig. 3 which also adapt. said fulcra toact as members for assembling the frame. As indicated in Figs. 1 and 2, said inner sustaining-pawl is normally kept in contact with the inner ratchet teeth 41 of the ram 43 by a compression spring 54: contained 7 in the lug 55 piercingly secured through both halves of the frame by bolts 56 having nuts 57 and said outer locking-pawl 52 is normally keptin engagement with the outer ratchet teeth i2'by the compressionspring 58 in the lug 59 piercingly secured through both halves of the bifurcated frame by the bolts 60 having nuts 61.

Referring to Fig. 2 the toggle-link 62 is journaled at itsend in the toggle-pin 63,

cured in the top of the outer lifting-ratchet 40, and is articulated at its inner end. bythe knuckle-pin 64 which commonly engages with the inner end of the toggle-lever 65 jointed to the toggle-pin 66' secured near the top of the inner lifting-pawl 38. The purpose of this toggle mechanism is to release both said inner lifting-pawl 38 and outer lifting-pawletl from engagement with the 74 in said walking-link.

respective inner ratchet-teeth'dl andouter ratchet-teeth 42 of the ram 4:3 and to lock the same out of engagement by depressing said toggle lever 65 so as to straighten the toggle as is done when it is desired to lower a load resting upon said ram 43.

Referring to Figs. 2, 3, and 5, the powercrank 6 bears coextensively above the slot 10 the extension'arin' 67 having the slotted fork 68, which is adapted to receive the walking-link 69. The demountable pin '70, is capable of being inserted in the endof said walkin -link 69 and of en 'a "in in As indicated in Figs. 2 and 3, the ram 43, within the frame 1", slides on either side between guides such as the upper guide 7 5, intermediate guide 76, and lower guideW, coextensively formed within the bifurcated half-frame 2, and by an oppositely registering upper guide 78, intermediate guide 79,

and lower guide 80, coextensively formed on the inside of the opposite half-frame 3, thesaid guides being engaged by oppositely registering slots 81, 82, made in the sides of the ram 43. V

Referring to Fig. 2, the function, of said pushing and pulling slots 72, 74; with their respective intermediate pins 71 and 7 3 may be exemplified thus: WVhen lowering a load,

a slight depression of the power-crank 6, first draws outward the walking-link 69, causing the intermediate pin'71 to withdraw the sustaining-pawl 50 from engagement with the ratchet-teeth il, which teeth are positioned one-half pitch below the opposite ratchet-teeth 422, which therefore permits the ram 43 to drop one-half pitch, so that the ratchet-teeth 42 rest upon the opposite sustaining-pawl 52. During this mo tion, the pushing slot 74 has overtaken said intermediate pin 73, but, as the sustainingpawl 52 now snapsin'to engagement, said in termediate pin 73again rests at the inner end of said pushing slot 74, as shown in Fig. 2. hen the power-crank 6 is now slightly lifted, it pushes said walking-link 69, and in so doing engages said intermediate. pin 73, and while the opposite pulling-slot '42 runs idle, pushes out from engagement with the outer ratchet-teeth t2 the, outersustainingpawl 52, thus permittingthe ram 43 to descend by the distance of cnehalf pitch of the opposite inner ratchet-teeth al, which returns the parts to the relative positions drawn in Fig. 2.

In order to prevent any injurious shock being sustained when large loads of many tons are lowered on the ram 43 which might result in gradual injury to ratchet-teeth 41 and 42, I employ the following mechanism, as clearly illustrated in Figs. 2 and 3: The dash-pot 83, bored into the lower end of the ram 48, has fitted therein the long dash-pot plunger 84, having a shouldered reduction 85 at the base thereof, fitting tightly within a bore in the base-boss 86, upon which rests the butt 87 of the ram 43 when returned to the bottom of its stroke. An air orifice 88 near the top of said dash-pot 83 gives ingress and egress of air to the dash-pot. When a load is being raised the dash-pot 83 is steadily filled with air through the air orifice 88, but when a load is being lowered by operation of the walkingdink (39, as described in the previous paragraphs, the air in said dash-pot 83 is quickly compressed and acts to cushion the descent of the ram 43 as the respective sustaining-pawls 50, 52 are released from engagement with the ratchetteeth 41, 42 by said walking-link, thus permitting the ram and its load to have a cushioned descent, as the compressed air very gradually escapes through the air-orifice 88, and so preserves the ratchet-teeth from injury and the load from shock.

Referring to Figs. l and 5 an intermediate spacing sleeve 90 is employed on the beam fulcrum-pin 31 to laterally space the halves of the lifting lever 27, so that the same shall aline parallel to the outer faces of the delivery-arm 22 of the secondary tractor-levers 28, thus laterally securing said halves of said lifting beam between said intermediate spacer and the thin washers 30, as clearly shown in Fig. 5.

The operation of my invention is as follows: Whenever the frame 1 has been seated in any position such as on a road-bed, blocks or other base, and the jack has been slid with its ram 48 beneath the load to be raised, with the demountable pin removed from the walkinglink 69, and the handle 4: inserted in the socket 5, and both the liftingpawls and sustaining-pawls in engagement, the power-crank 6 is depressed by operation of said handle, the force imparted therefrom transmitting through the connecting link 12, which, pulling upon the primary knucklepin 13, bends the straightened primary tractor-levers 16, sustained from the primary suspension-pin 17, and causes said tractorlevers to exert in a straightened upward direction a greatly augmented pressure through the knuckle-pin 20, which bends the straigh ened secondary tractor-levers 23 sustained on the secondary suspension pin 2a and causes said secondary tractor-levers to exert a vastly intensified force through the secondary delivery-pin 29, which is transmitted around the fulcrum-pin 31, and through the lifting-beam 27 which thus converts this pulling effort into a powerful lifting efiort which is imparted through the yoke-pin 35 to the duplex pawl-yoke 36, and thence through the lifting-pawls 38 and 40, pivoted thereon, which pawls being staggered with the inner pawl 38 thereof one-half pitch in advance of the outer pawl 40, causes each upward impulse of said yoke-pin' from said lifting-beam to lift, by the space of onehalf pitch of the ratchet-teeth 41 and 42, in alternation, the ram 43. As the respective lilting-pawl 50 pivoted on the fulcrum-pins 4:9 and 52 pivoted on the fulcrum-pin 51 are also staggered with the inner thereof one-half pitch in advance of the outer thereof, they synchronously drop into place in engagementwith the respective ratchet-teeth 41 and 4-2, in alternation, as said ram 43 is raised by the amount of one-half tooth pitch, at each depression of the handle 4-, and so sustains the load at every position of lift.

When it is desired to lower a load, the toggle-link 62 and toggle-lever 65 are straightened by depressing the latter until same are in a straight line, which disengages the lifting-pawl 38 from the ratchetteeth t1 and the lifting-pawl 52 from the ratchet-teeth 42, leaving the load upheld exclusively by said sustaining-pawls 50 and 52. The demountable pin 70 is then inserted through the walking-link 69 and slotted fork 68 of. the power-crank 6, and the latter is very slightly oscillated, which causes the walking-link 69 to alternately push the inner sustaining-pawl 50 out of engagement with the inner ratchet-teeth e l, and the outer sustaining-pawl 52 out of engagement with the outer ratchet-teeth 4-2, thus lowering the load at each such movement by the distance of one-halt pitch of said teeth, the descent being meanwhile cushioned by the air imprisoned in the dash-pot 83 (Fig. 8), over the dash-pot plunger 84. It will be noted that the constant action of the powerful compression springs 54 engaging the inner sustaining-pawl 50 and 58 engaging the sustaining-pawl 52, in connection with the accurately spaced distance between said pawls andfbetween the pushing slot 72 containing the intermediate pin 71 the pulling-slot 74 having the intermediate pin 78 is such that it is impossible for the parts to ever occupy any position wherein one of the said two pawl is not in secure engagement with its adjacent ratchet-teeth, so that consequently the ram 43 may not under any circumstances slip past said pawls and cause a load on the ram 43 to drop suddenly on the dash-pot 83.

Having thus described my invention, I claim:

1. Combined in a jack a frame; a menually operable power-crank, pivoted in said frame; and inter-articulated dual sets of tractor-levers, adapted to be actuated by said power-crank, substantially as described.

2. Combined in a jack a frame; a manually operable power-crank pivoted in said frame, provided with a connecting-link; a primary set of tractor-levers suspensionally pivoted in said frame, adapted to be actuated bysaid power-crank and link; a secondary set of tractor-levers suspensionally pivoted in said frame, having a knuckle-pin thereof articulated to the delivery-pin of said primary set of tractor-levers, adapted to be actuated by said primary set of tractor levers;and lifting members, adapted to be actuated by said secondary set of tractor-levers, substantially as described.

8. Combined in a jack a frame; a manually operable power-crank pivoted in said frame, provided with a connecting-link; a primary set of tractor-leverssuspensionally pivoted in said frame, having the knucklepin thereof articulated to the delivery-pin of said primary set of tractor-levers, adapted to be actuated by said primary set of tractor-levers; a liftingbeam pivoted in said frame adapted to be actuated by said secondary set of tractor-levers; and a ram adapted to be actuated by said lifting-beam,

substantially as described.

4:. Combined in a jack a frame; a manually operable lifting linkage pivoted in said frame; a lifting yoke having pivoted thereon duplex lifting-pawls, adapted to be actuated by said manually operable lifting linkage; a ram slidably guided in said frame provided with ratchets adapted to be engaged-by said lifting-pawls; and, pivot-ally fixed in said frame, duplex lifting-pawls adapted to engage the ratchets on said ram adapted to sustainingly engage the ratchets on said rain as the latter is actuated by said liftin -pawls. I

5. Combined in a jack a frame; a manually operable power-link provided with a connecting-link; inter-articulated primary and secondary sets of tractor levers, each set being suspensionally. pivoted in said frame, capable of being actuated by said power-crank and link; a duplex liftingbeam, pivoted in'said frame, capable of being operated by the action of the secondary of said sets of tractor-levers; a duplex pawlyoke pivoted within said duplex liftingbeam, having pivoted thereon spring actuating lifting-pawls; and a ram slidably guided in said frame having thereon ratchets adapted to be engaged by said lifting-pawls, substantially as described. 7

6. Combined in a jack, a frame; a manually operable lifting-linkage, comprisingsuspensionally pivoted, interarticulated tractor-levers and a lifting-beam adapted to 1 ,eo eos be actuated thereby; duplex pawl-yoke, pivoted to said lifting-beam having pivoted thereon duplex spring actuated liftingpawls; a ram slidably guided in said frame, provided with ratchets adapted to be engaged by said duplex lifting-pawls; and pivotally fixed in said frame, duplex spring actuating sustaining-pawls, adapted to sustainingly enga c said ratchets on said ram, as the latter is actuated by said liftingpawls, substantially as described.

7. Combined in a jack, a frame; a manually operable lifting-linlrage, comprisin suspensionally pivoted, inter-articulated V tractor-levers and a lifting-beam adapted to be actuated thereby; duplex pawl-yoke, pivoted to said lifting-beam having pivoted thereon duplex spring actuated liftingpawls; a ram slidably guided in said frame, provided with ratchets adapted to be en gaged by said duplex spring actuating sustaining-pawls, adapted to be engaged. by said duplex lifting-pawls; pivotally fixed in said frame, duplex spring actuating sustaining-pawls, adapted to sustainingly engage said ratchets on said ram, as the latter is actuated by said liftingpawls; and a selfcontained pneumatic dash-pot in said ram, having the plunger thereof sustained by said frame, adapted to cushion the motion of said ram during the retraction thereof, substantially as described.

8. Combined in a jack, a frame; a manu ally operable lifting-linkage, comprising suspensionally pivoted, inter-articulated tractor-levers and a lifting-beam adapted to be actuated thereby; duplex pawl-yoke, pivoted t0 said lifting-beam having pivoted thereon duplex spring actuated liftingpawls; a ram slidably guided in said frame, 7

provided with ratchets adapted to beengaged by said duplex spring actuating sustaining-pawls, adapted to be engaged by said duplex lifting-pawls p'ivotally fixed in said frame, duplex spring actuating sustaining-pawls, adapted to sustainingly en-' gage said ratchets on said ram, as the latter is actuated by said lifting-pawls; togglemembers, pivoted to said lifting-ratchets adapted to lock same out of engagement with said ratchets on said ram; and a releasing-member adapted to alternately release said sustaining-pawls from engagement with said ratchets on said ram to permit the retraction thereof within said ram, substantially as described.

In witness whereof, I have hereunto set my hand and seal at Indianapolis, Indiana, this 16th day of October, A. D. nineteen hundred and twenty.

CHARLES bl. HOWLANiE-SHEARMAN.

Witnesses:

' CAanYfS. FRYE, M. L. SHULER. 

